Joe Decuir's 1977 engineering notebook from when he worked at Atari, including design concepts (lots on the Atari 2600 and Atari 400/800) feasibility studies, meeting notes, teardown of competing products (such as VIC-20, TI 99/4A)
Scanned from Joe's photocopy of his notebook with his permission. At some point, Joe was made to turn the original notebook into Atari management, but he made these photocopies first. Some pages are not of the quality that we might prefer. The scans look just as good as the photocopies.